/*
 * Copyright 2011, Blender Foundation.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * Contributor: Campbell Barton
 */

#include "MEM_guardedalloc.h"

#include "COM_DespeckleOperation.h"

#include "BLI_utildefines.h"

DespeckleOperation::DespeckleOperation() : NodeOperation()
{
	this->addInputSocket(COM_DT_COLOR);
	this->addInputSocket(COM_DT_VALUE);
	this->addOutputSocket(COM_DT_COLOR);
	this->setResolutionInputSocketIndex(0);
	this->m_inputOperation = NULL;
	this->setComplex(true);
}
void DespeckleOperation::initExecution()
{
	this->m_inputOperation = this->getInputSocketReader(0);
	this->m_inputValueOperation = this->getInputSocketReader(1);
}

void DespeckleOperation::deinitExecution()
{
	this->m_inputOperation = NULL;
	this->m_inputValueOperation = NULL;
}

BLI_INLINE int color_diff(const float a[3], const float b[3], const float threshold)
{
	return ((fabsf(a[0] - b[0]) > threshold) ||
	        (fabsf(a[1] - b[1]) > threshold) ||
	        (fabsf(a[2] - b[2]) > threshold));
}

void DespeckleOperation::executePixel(float output[4], int x, int y, void * /*data*/)
{
	float w = 0.0f;
	float color_org[4];
	float color_mid[4];
	float color_mid_ok[4];
	float in1[4];
	int x1 = x - 1;
	int x2 = x;
	int x3 = x + 1;
	int y1 = y - 1;
	int y2 = y;
	int y3 = y + 1;
	CLAMP(x1, 0, getWidth() - 1);
	CLAMP(x2, 0, getWidth() - 1);
	CLAMP(x3, 0, getWidth() - 1);
	CLAMP(y1, 0, getHeight() - 1);
	CLAMP(y2, 0, getHeight() - 1);
	CLAMP(y3, 0, getHeight() - 1);
	float value[4];
	this->m_inputValueOperation->read(value, x2, y2, NULL);
	//const float mval = 1.0f - value[0];


	this->m_inputOperation->read(color_org, x2, y2, NULL);

#define TOT_DIV_ONE 1.0f
#define TOT_DIV_CNR (float)M_SQRT1_2

#define	WTOT (TOT_DIV_ONE * 4 + TOT_DIV_CNR * 4)

#define COLOR_ADD(fac)  \
{ \
	madd_v4_v4fl(color_mid, in1, fac); \
	if (color_diff(in1, color_org, this->m_threshold)) { \
		w += fac; \
		madd_v4_v4fl(color_mid_ok, in1, fac); \
	} \
}

	zero_v4(color_mid);
	zero_v4(color_mid_ok);

	this->m_inputOperation->read(in1, x1, y1, NULL); COLOR_ADD(TOT_DIV_CNR)
	this->m_inputOperation->read(in1, x2, y1, NULL); COLOR_ADD(TOT_DIV_ONE)
	this->m_inputOperation->read(in1, x3, y1, NULL); COLOR_ADD(TOT_DIV_CNR)
	this->m_inputOperation->read(in1, x1, y2, NULL); COLOR_ADD(TOT_DIV_ONE)

#if 0
	this->m_inputOperation->read(in2, x2, y2, NULL);
	madd_v4_v4fl(color_mid, in2, this->m_filter[4]);
#endif

	this->m_inputOperation->read(in1, x3, y2, NULL); COLOR_ADD(TOT_DIV_ONE)
	this->m_inputOperation->read(in1, x1, y3, NULL); COLOR_ADD(TOT_DIV_CNR)
	this->m_inputOperation->read(in1, x2, y3, NULL); COLOR_ADD(TOT_DIV_ONE)
	this->m_inputOperation->read(in1, x3, y3, NULL); COLOR_ADD(TOT_DIV_CNR)

	mul_v4_fl(color_mid, 1.0f / (4.0f + (4.0f * (float)M_SQRT1_2)));
	//mul_v4_fl(color_mid, 1.0f / w);

	if ((w != 0.0f) &&
	    ((w / WTOT) > (this->m_threshold_neighbor)) &&
	    color_diff(color_mid, color_org, this->m_threshold))
	{
		mul_v4_fl(color_mid_ok, 1.0f / w);
		interp_v4_v4v4(output, color_org, color_mid_ok, value[0]);
	}
	else {
		copy_v4_v4(output, color_org);
	}
}

bool DespeckleOperation::determineDependingAreaOfInterest(rcti *input, ReadBufferOperation *readOperation, rcti *output)
{
	rcti newInput;
	int addx = 2; //(this->m_filterWidth - 1) / 2 + 1;
	int addy = 2; //(this->m_filterHeight - 1) / 2 + 1;
	newInput.xmax = input->xmax + addx;
	newInput.xmin = input->xmin - addx;
	newInput.ymax = input->ymax + addy;
	newInput.ymin = input->ymin - addy;

	return NodeOperation::determineDependingAreaOfInterest(&newInput, readOperation, output);
}